Multi-Phase Flow Metering and Water Cut Testing Device and its Application in CO2 Huff & Puff Wells

Abstract CO2 stimulation is a production stimulation technology that utilizes the expansion, extraction, and dissolution of CO2 to replenish formation energy, increase recovery, increase oil well production in high water-cut heavy oil and bottom water reservoirs. It is also an excellent carbon sequestration method, has become a research hotspot in recent years. The water cut of wellhead multi-phase flow rate are important parameters for calculating CO2 stimulation efficiency, evaluating the effect of CO2 stimulation, and carrying out working condition diagnosis. However, the existing water cut sampling and testing methods, in oil fields have several problems such as low efficiency, poor precision, low frequency, changes in fluid physical properties during the sampling process, and high cost, which cannot meet the requirements. In addition, currently, for the gas-liquid two-phase flow and even the oil, gas and water three-phase flow produced by CO2 huff & puff Wells, three-phase separator metering technology is generally used. The frequency and accuracy of the metering are not high, making it difficult for engineers to accurately understand the production dynamics of oil and gas wells. The series of CO2 huff & puff wells water cut, or multi-phase flow rate measurement methods and devices based on water cut meters or multi-phase flow-meters are proposed, which solves the problem of online, high-frequency, and accurate measurement of water cut or three-phase flow in huff and puff wells in an integrated manner. The proposed method of diagnosing the working conditions of carbon dioxide huff and puff wells based on multi-parameter water cut meter can realize the "gas slug", "continuous pumping and spraying", "oil blockage", "gas continuous phase", "ice blockage" and other working conditions diagnosis and alarm, that occurs in carbon dioxide huff and puff wells during the production stage, and proposes "monitoring and observation", "exhaust pressure control", "hot washing", "Variable flush times", "heating pipeline" and other corresponding treatment methods.